The adhesion of polyvinylidene fluoride (hereinafter PVF.sub.2) to other polymers is generally minimal or nonexistent. This enables PVF.sub.2 to be used as an unmolding surface (stripping surface) for certain resins even at very high temperatures.
To effect adhesion of other polymers to PVF.sub.2 it is necessary to use expensive and extensive treatments of the PVF.sub.2 surface which treatments are, therefore, not commercially satisfactory.